PDCD1 and neoplasm: A study by Gallazzi et al. on tumor associated circulating NK (TANK cells) in prostate cancer showed that these types of NK cells with CD56brightCD9+CD49a+CXCR4+ phenotype are expressing TIM-3 and PD-1 and they also produce proangiogenic factors and induce CXCL8, intercellular adhesion molecule 1 (ICAM-1) mRNA expression and vascular cell adhesion protein 1 (VCAM-1) in endothelial cells.